Electrical receptacle, plug, and switch



Dec. 29, 1953 J. D. HARLIN ELECTRICAL RECEPTACLE, PLUG, AND SWITCH Filed May 15, 1950 NM( M M Mm,

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uw@ @u @uw .QN mm LN Patented Dec. 29, 1953 ELECTRICAL RECEPTACLE, PLUG, AND SWITCH J. D. Harlin, Indianapolis, Ind., assignor to Harlin Brothers, Indianapolis, Ind., a partnership Application May 13, 1950, Serial No. 161,768

5 Claims.

cause the production oi undesirable squealing or vscreeching noises in the public address system if the active electrode of the conductor device accidentally comes into electrostatic relationship with an electrified object when disconnected `from the jack receptacle or socket with which it is designed for intertting connection. The mere accidental touching of the active electrode of a jack by a person in handling the same may result Y in the production of such undesirable noises in the broadcasting system with which the jack is electrically connected, since the person touching the active electrode of the jack constitutes an electrostatically charged object.

An important object of the present invention is to provide an electrical connector device hav-Y ing means incorporated therein for conditioning the same to prevent the production of screeching noises in a sound producing system with which it is connected, if and when the jack should come into noise producing relationship M- with an electrified body when disconnected from its receptacle socket. Y

Another important object is to provide a connector of the character mentioned with a simple, inexpensive, short-circuiting switch, normally serving to disable the jack when the same is disconnected from its cooperating receptacle socket, and operable upon insertion of the jack in its socket to condition the connector mecha nism for operation in required fashion.

Another important object is to provide a jack plug with a normally closed short-circuiting switch, openable, upon insertion of the jack plug in its cooperating receptacle socket, to condition the connector device for normal operation.

The foregoing and numerous other important objects, advantages, and inherent functions of the invention will become apparent as the same is more fully understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment of the invention.

Referring to the drawings:

Fig. 1 is a sectional View through a jack plug and its cooperating receptacle socket, showing the parts in relatively connected position;

Fig. 2 is a sectional view taken substantially along the line 2-2 in Fig. l, to illustrate plug conditioning means embodying the present invention; and

Fig. 3 is an enlarged sectional View of a portion of the structure shown in Fig. 2.

To illustrate the invention, the drawings show connector mechanism II comprising a jack plug I2 and a cooperating receptacle socket structure I3.

While the device of the present invention is particularly adapted for connecting a radio type amplifier with a musical instrument or the like,

"f it will be obvious that the present invention is not necessarily limited to such use, but may have useful application wherever the facilities contemplated by the present invention may be desirable. A

While the receptacle I3 may comprise any preferred construction providing a pair of relatively insulated electrodes I4 and I5 for engagement and electrical connection respectively with cooperating electrode elements I6 and I'I of the jack plug I2, the receptacle structure may be formed as shown in Fig. 1, in which the electrode I4 comprises a sleeve adapted to snugly and slidingly receive the electrode stem of the jack plug, for frictional engagement and electrical contact with the electrode element I6 thereof.

To this end, the electrode I4 may comprise a cylindrical element I8 of electrical conducting material, having a peripheral outstanding ange I9 medially of the ends thereof, the outer surfaces of the element I8 being screw threaded, as at 20, between the flange I9 and the outer end 2I thereof, the element I8, between the ilange I9 and the opposite or inner end 22, being finished with a smooth, preferably cylindrical outer surface upon which a plurality of disk-like elements or washers may be assembled and secured in stacked relation.

These disk-like elements may include a Washer 23 of suitable insulating material, snugly encircling the element I8 in position resting against and supported by the liange I9. If desired, the washer 23 may have a central embossment 23. forming an annular shoulder encircling the ele- Vment I8 in position to support a disk 24 of electrical conducting material upon the Washer 23,

in position concentric with respect to and insulated from the sleeve element I8. A washer of insulating material may also be assembled upon the element I8 in position to hold the disk 24 in place on the washer 23. The washer 25 also may be provided with a central embossment 25', forming an annular shoulder encircling the element I8 in position to support a disk 26 of electrical conducting material upon the washer 25, in position concentric with respect to 'f and insulated from the sleeve element I8. A washer 21 of insulating material may also be assembled upon the element I8 in position to hold the disk 25 in place on the washer 25. A disk 2E; of electrical conducting material may also be assembled upon the element I3, in position resting against the washer 2l, and the inner end 22 of the element I8 may be peened over upon the disk 28, as shown, in order to clarnpingly hold the disks and washers in assembled relationship upon the element I8 between the flange It and the peened end 22.

The disks 24, 2 and 28 may each respectively be provided with soldering lugs 24', 25 and 28 for electrically connecting the same, as with wave generating or other electrical translation means. The disk 24, also, may be provided with a resilient extension 29, comprising a finger extending from the edge of the disk in a direction parallel with respect to the axis of the sleeve element I8, said extension having an inwardly bent portion 3i) and a portion 3| forming the electrode I5, said electrode portion being normally disposed opposite the end of the element I8, at an inclination with respect to the axis thereof, and formed with a cup-like depression 32 adapted to interttingly engage and electrically Contact with the electrode element I1 of the jack plug, when the same is fully positioned in the receptacle socket. gaged, the linger 29 and the electrode portion 3| occupy the positions shown in solid lines in Fig. 1; but normally occupy the position shown in dotted lines when the jack plug is retracted from the socket.

The disk 28 also may be provided with an extension forming a finger 33 extending adjacent and parallel with respect to the nger 29. One of said fingers may be provided with an oset projection 34 extending toward the other ringer, in position to engage and make electrical contact therewith when the finger 29 is in the dotted line position, such contact being broken upon the insertion of the jack into operative position in the receptacle. 1f desired, also, a washer 35, of thininsulating material, may be secured on the element I8 between the disk 28 and the washer 2, said washer having a marginal tab 35 extending between the edge of the disk 28 and the linger 33 in order to assure against electrical contact therebetween.

The threaded portions 2lir of the sleeve element I8 aiord means for mounting the receptacle, as on a support panel 3l, formed with an opening 38 sized to freely receive the threaded portion of the element I8, whereby said threaded portion may be inserted through the opening 38 in the panel and the receptacle assembly clamped upon the panel between the fiange I9- and a clamping nut 39 applied to the projecting threaded endA o1 the sleeve I8, a washer 40 being preferably assembled upon the panel, around the sleeve I8 behind the clamping nut 39. So mounted, the receptacle will be supported with the outer end 2| oizV the sleeve I5 in position exposed on one When so enside of the panel for the reception of the stem of the jack plug I2 in the opening or channel provided by the sleeve element I8, said outer end 2l of the sleeve forming an annulai` shoulder defining the receptacle opening.

The jack plug I2, as shown, comprises a preferably circular plate or head 4I, having a central opening 42 in which the end of altube 43 of electrical conducting material Vis press fitted. This tube 43 extends axially of the head 4I and forms the electrode element I6 of the jack plug, said element being sized to frictionally t within Y and electrically contact with the sleeve I8 of the receptacle socket. The end of the element 43 remote from the head 4I carries a washer 44 of insulating material; and the tube is fitted with a tubular lining 45 of insulating material preferably throughout its entire length from the washer 44 to and slightly beyond the opposite end of the tube 43.

A pair of connector elements 4E, 45', of electrical conducting material, each having a disk portion 4l, 4l', and 'a conductor attaching lug 48, 48', are assembled in stacked relationship on the head 4I in concentric relation with the end of the tube 43. To this end, the disk 41 engages and electrically contacts with the head V4I and the connected end of the sleeve 43, the end of the insulating sleeve 45 extending within said disk, a washer 49 of Vinsulating materialoverlies the disk-4i, and the disk 4l overlies the washer 48, the parts being clampingly secured'together by means of an elongated threaded stud 50 oi electrical conducting material, having a head 5I overlying and electrically connecting the disk 4l and a shank extending through the tube 43 and the insulating sleeve 45, as well as the disk 44, and having threaded engagement and electrical contact with a generally spherical, knoblike element 52 of electrical conducting material forming the electrode element Il.`

It will be seen from the foregoing that the electrode element I6 is electrically connected with the lug 46; that the electrode element I`|- is electrically connected with the lug 46'; and that the said electrodes and lugs are relatively insulated by means of the washers 44 and 49 and the sleeve 45. The portions 48 and 4B of the lugs 46k and 46' may be fitted with clamping screws 53 and 53 for the electrical connection of the electrodes I6 and Il with conductors leading to a sound reproducing system, in order to connect the system with a sound impulse generator, of which the receptacle structure forms an outlet, by inserting the jack plug in operative circuit forming position in the socket.

As a safety measure, the electrode element I6 and its connection terminal 48 should` be connected with the low o r groundedr side of thetranslation system with which it is used; and the yelectrode element Il should be connected with the high, active or hot lside of the system. Whenso connected, conditions resulting in the production of howling noises in the sound producing device of the system wm be established if the hot electrode element I'll cornesV into electrostatic relationship with an electrifiedv object, esfwhen 'seid electrode is touched by the person handling the jack plug, or if the hot electrode is accidentally or otherwise brought into engagement with,`4or into close proximity to, any electrified body,l and particularly bodies having an, electrostatic or condenser action. y

In order to eliminate the unwanted production of such howling or screeching noises, the

present invention contemplates the provision of means for conditioning the jack plug to render it incapable of causing such noises when accidentally touched, or otherwise brought into prox- -imity with electried objects, at all times when it is disconnected from the cooperating receptacle socket structure. To this end, as shown more particularly in Figs. 2 and 3, a channel 54, having an axis parallel with respect to the axis of the plug prong, is formed through the head 4I, the

terminal disks41 and 41', and the insulating vWasher 49. This channel is disposed in position so that, when the jack plug is inserted in the socket structure, the axis of the channel is in alinement with the rim 2| of the socket structure, regardless of the relative angularity of the .plugwith respect to the socket structure; and

said channel may be formed partially in the sleeve member 43, which may have a groove 55 forming a part f the channel. The portions 56, 51 and 58 of the channel 54, which extend respectively in the head 4I the disk 41', and the Washer 49, are relatively large as compared with the channel portion 59 through the disk 41.

A pin or stem 60 of electrical conducting material, sized to snugly, yet slidingly fit the channel portion 59, is mounted in the channel. Said pin has a head 6I at one end overlying the end fof the channel opening through the disk 41', so

that the marginal portions of said head may engage and make electrical contact with the disk 41' at a seat 62 formed thereon at and around the end of the channel. The opposite end of the stern 60 is also provided with an integral head 63 which projects beyond the opposite end of the channel, which opens on the face of the head 4I. Resilient means, preferably a helical spring 64 encircling the stem 60, within the channel portion 56, and bearing at its opposite ends upon the head 63 and the disk 41 around the channel portion 59, is provided to normally urge the stem 60 in the channel in a direction to engage the head 6I on the seat 62.

From the foregoing, it will be seen that the stern 60 will at all times be electrically connected with the disk 41, and hence with the electrode element I6 and the connection terminal 48. The stem Will also be electrically connected through the head 6I with the disk 41', and hence with the electrode element I1 and the connection terminal 48', so long as the head 6I is in electrical engagement with the seat 62, under the inuence of the spring 54. Upon the insertion of the jack plug I2 fully into the socket structure, into position therein engaging the electrode elements I5 and I 1, the head 63 of the pin 66 will engage and be depressed by the rim 2I of the socket structure. When so depressed against the inuence of the spring 64, the pin will be axially shifted in the channel 54 in a direction to disengage the head 6I from the seat 62, thereby breaking electrical connection of the pin with the disk 41', the electrode element I1, and the connection terminal 48'.

It will be noted that the pin 60 is guided in the channel 54 by snug, sliding engagement within the channel portion 59, and hence is held in position out of contact with the disk 41 except when the head 6I is in engagement with the seat 62. If desired, a sleeve or sleeves 65 of insulating material may be disposed around the stem 60 within the enlarged channel portions 51 and 58, in order to assure the insulation of the stem from the disk 41'; and the channel portion 51 in the insulating washer 49 may, of course, be formed to snugly receive the stem 60, if desired.

The head 4I may be threaded, as at 66, for detachable engagement with a preferably cylindrical cover member 61, and a sleeve of insulating material 68 may be disposed within the cover member in position enclosing the connection ter-4 minals 48 and 48'.

The operation of the pin 60 in the manner described serves to electrically interconnect, and thus short-circuit, the hot electrode with the grounded electrode of the plug, at all times when the jack plug is disconnected from its cooperating socket structure, thereby assuring against the production of howling noises in the sound reproducing system with which the plug is used. Whenever the jack is in operative position in its cooperating socket structure, the electrode elements I6 and I1, however, are and remain electrically disconnected for normal circuit forming operation.

It is thought that the invention and its numerous attendant advantages will be fully understood from the foregoing description, and it is obvious that numerous changes may be made in the form, construction and arrangement of the several parts without departing from the spirit or scope of the invention, or sacrificing any of its attendant advantages, the form herein disclosed being a preferredembodiment for the purpose of illustrating the invention.

The invention is hereby claimed as follows:

l. An electrical connector comprising a jack plug device having a body and a projecting prong formed for interfitting engagement with a cooperating connector structure having a prong receiving cavity and a rim dening the open end of said cavity, said prong comprising a pair of relatively insulated contact elements adapted for connection making contact with corresponding contacts of the cooperating connector structure when interfltted therewith, a stem of electrical conducting material mounted on said body, electrically connected with one of said contact elei ments and axially slidable into and out of elecand to present an end of` said stem in position projecting from a face of said device for stem depressing engagement with the rim of the co operating connector structure, to disconnect said stem from said other contact element when said device is interittingly engaged with said cooperating connector structure.

2. An electrical connector device, formed for intertting engagement with a cooperating connector structure and comprising a pair of relatively insulated contact elements adapted for connection making contact with corresponding contacts of the cooperating connector structure when intertted therewith, a pair of stacked members electrically connected respectively with said contact elements, a layer of insulation disposed between said members, said layer and members having a channel therethrough, a stem of electrical conducting material axially slidable in said channel in electrical contact with one of said members and out of electrical contact with the other member, said stem having a head adapted to engage and disengage a seat formed on said other member, and spring means normally urging said stem in a direction to engage said head with said seat at one end of said channel, whereby to electrically connect said members through said stem and seated head, and to project the head remote end of the stem at the opposite end of the channel in position for stem depressing engagement With the cooperating connector structure, to disconnect said head from said seat and electrically isolate said menibers when the device is interfittingly engaged with said cooperating connector structure.

3. An electrical connector comprising a plug device having a pair of relatively insulated conltact elements and a cooperating receptacle socket structure adapted for intertting engagement with said plug to electrically connect the contact elements thereof respectively with cooperating contacts of the socket structure, said plug embodying a pair of stacked members electrically connected respectively with said contact elements, a layer of insulation disposed between said members, said layer and members having a channel therethrough, a stem of electrical conducting material axially slidable in said channel in electrical contact With one of said members and out of electrical contact with the other member, said stem having a head adapted to engage and disengage a seat formed on said other member, n

and spring means normally urging said stem in a direction to engage said head with said seat at one end of said channel, whereby to electrically connect said members through said stem and seated head, and to project the head remote end of the stem at the opposite end of the channel in position for stem depressing engagement with the cooperating connector structure, to disconnect said head from said seat and electrically isolate said members when the device is interfittingly engaged with said cooperating connector structure.

4. An electrical connector comprising a jack plug device having a body and a projecting prong providing a pair of relatively insulated contact I.

elements respectively at the body remote end of and in the lateral portions of said prong, and a receptacle socket structure having a rim denning a cavity for interttingly receiving said prong and providing contacts for electrical connection respectively with the said contact elements of the jack plug, a pair of stacked members electrically connectedA respectively with said contact elements, a layer of insulation disposed between said members, said layer and members having a channel therethrough, a stern of electrical conducting material axially slidable in said channel in electrical Contact With one of said members and out of electrical contact with the other member, said stem having a head adapted to engage and disengage a seat formed on said other member. and spring means normally urging said stem in a direction vto engage said head with said seat at one end of said channel, whereby to electrically connect said members through said stem and seated head, and to project the head remote end of the stem at the opposite end of the channel in position for stem depressing engagement with said rim, to disconnect said head from said seat and electrically isolate said members when the device is interttingly engaged With said cooperating connector structure.

5. An electrical connector comprising a jack plug device having a body and a projecting prong formed for intertting engagement in a prong receiving cavity of a cooperating receptacle socket structure, said device comprising a pair of relatively insulated contact elements, including a sleeve and a knob respectively forming the sides and the body remote end of the prong and positioned to make electrical connection with corresponding contacts of the socket structure when interfitted therewith, a pair of stacked members on said body and electrically connected respectively with said contact elements, a layer of insulation disposed between said members, said body, layer and members having a channel therethrough, a stem of electrical conducting material axially slidable in said channel in electrical contact with one of said members and out of electrical contact with the other member, said stem having a head adapted to engage and disengage a seat formed on said other member, and spring means normally urging said stem in a direction to engage said head with said seat at one end ci" channel, whereby to electrically connect said members through said stem and seated head, and to project the head remote end of the stem from said body at the opposite end of the channel in position for stem depressing engagement with the cooperating connector structure, to disconnect said head from said seat and electrically isolate said members when the device is interttingly engaged with said cooperating connector structure.

J. D. HARLIN.

References Cited in the le 0f this patent UNITED STATES PATENTS Number 

